A Company Claims That 9 Out of 10 Doctors (I $90 \%$

Multiple Choice

A company claims that 9 out of 10 doctors (i.e., $90 \%$ ) recommend its brand of cough syrup to their patients. To test this claim against the alternative that the actual proportion is less than $90 \%$ , a random sample of doctors was taken. Suppose the test statistic is $z = - 2.23$ . Can we conclude that $H _ { 0 }$ should be rejected at the a) $\alpha = .10$ , b) $\alpha = .05$ , and c) $\alpha = .01$ level?

A) a) no; b) no; c) no
B) a) yes; b) yes; c) yes
C) a) no; b) no; c) yes
D) a) yes; b) yes; c) no